Safe Driving Principles and Hazard Perception
Core concepts
Safe driving rests on observation, anticipation, and space. The key ideas are stopping distance (reaction distance plus braking distance), safe following distance, and the two-second rule in good conditions, extended in rain, ice, or poor visibility. Candidates must understand how speed, road surface, tyre condition, and load affect braking, and how fatigue, alcohol, and distraction degrade reaction time.
Hazard perception
Scan far ahead and use mirrors regularly; look for developing hazards such as pedestrians near crossings, children near parked cars, cyclists at junctions, and vehicles emerging from side roads. Vulnerable road users - pedestrians, cyclists, motorcyclists, and children - deserve extra space and lower speed. Overtaking must be planned so it can be abandoned safely.
Traps in questions
- The two-second rule is a minimum in ideal conditions, not a target in rain.
- Reaction distance grows with speed even if braking distance is unchanged.
- A hazard that has not yet moved (a parked car with a driver inside) may still be a developing hazard.
- Fog and rain reduce visibility and grip simultaneously; slow down more than you think.
Worked example
At 60 km/h a car travels about 17 m per second. With a one-second reaction time and a two-second gap, the safe gap is roughly 34 m. In rain, double the gap to about four seconds.